Stator of torque converter for vehicles improved to suppress separation of working fluid

Abstract

To suppress a separation of working fluid from the vane surface during operation at and around a fluid coupling condition attained after a substantial completion of torque conversion, the aerofoil and the array of stator vanes of a torque converter for vehicles are arranged such that a pressure side leading edge area and a suction side trailing edge area of the vane respectively satisfy the following conditions based upon the parameters assumed in FIG. 2: (D.sub.L -D.sub.LMIN)/D.sub.LSL ≦0.38(X.sub.L /S.sub.L -0.08).sup.1. 7 (D.sub.T -D.sub.TMIN)/D.sub.TST ≦0.36(X.sub.T /S.sub.T -0.45).sup.1. 7

We claim: 
     
       1. A stator of a torque converter for vehicles, comprising stator vanes each having such an aerofoil configuration and being arranged in such an array that, with respect to an area adjacent to a leading edge (L 1 ) of a pressure side surface of a first one (V 1 ) of said array of stator vanes, as viewed in a change of diameter (D L ) of a circle tangentially contacting with both said pressure side leading edge area surface of said first stator vane (V 1 ) and an inlet stream line (F a ) of working fluid directed to a leading edge (L 2 ) of a second one (V 2 ) of said array of stator vanes downstream of said first stator vane (V 1 ) along a flow of the working fluid, said circle substantially satisfies the following condition, for the purpose of suppressing a separation of the working fluid from said pressure side leading edge area surface of said first stator vane (V 1 ) in a fluid coupling condition attained after a substantial completion of torque conversion and therearound, against a shifting thereof between a position of X L  =0.08S L  from a cross point (M) of a perpendicular extended from the leading edge (L 1 ) of said first stator vane (V 1 ) to said inlet stream line (F a ) and a position where it traverses the leading edge (L 2 ) of said second stator vane (V 2 ):   (D.sub.L -D.sub.LMIN)/D.sub.LSL ≦0.38(X.sub.L /S.sub.L -0.08).sup.1.7     wherein   S L  is a distance from point M to leading edge L 2  along inlet stream line F a     X L  is a variable expressing distance from point M along inlet stream line F a     D L  is the diameter of the circle according to the above definition which tangentially contacts inlet stream line F a  at X L     D LMIN  is a minimum value of D L     D LSL  is the diameter of the circle according to the above definition which tangentially contacts inlet stream line F a  at a position of X L  =S L .   
     
     
       2. A stator of a torque converter for vehicles, comprising stator vanes each having such an aerofoil configuration and being arranged in such an array that, with respect to an area adjacent to a trailing edge of a suction side surface of a first one (V 2 ) of said array of stator vanes, as viewed in a change of diameter (D T ) of a circle tangentially contacting with both said suction side trailing edge area surface of said first stator vane (V 2 ) and an outlet stream line (F b ) of working fluid extending from a trailing edge (T 1 ) of a second one (V 1 ) of said array of stator vanes upstream of said first stator vane (V 2 ) along a flow of the working fluid, said circle substantially satisfies the following condition, for the purpose of suppressing a separation of the working fluid from said suction side trailing edge area surface of said first stator vane (V 2 ) in a fluid coupling condition attained after a substantial completion of torque conversion and therearound, against a shifting thereof between a position of X T  =0.45S T  from the trailing edge (T 1 ) of said second stator vane (V 1 ) and a position where it traverses a cross point (N) of a perpendicular extended from said trailing edge (T 2 ) of said first stator vane (V 2 ) to said outlet stream line (F b ):   (D.sub.T -D.sub.TMIN)/D.sub.TST ≦0.36(X.sub.T /S.sub.T -0.45).sup.1.7     wherein   S T  is a distance from trailing edge T 1  to point N along outlet stream line F b     X T  is a variable expressing distance from point T 1  along outlet stream line F b     D T  is the diameter of the circle according to the above definition which tangentially contacts outlet stream line F b  at X T     D TMIN  is a minimum value of D T     D TST  is the diameter of the circle according to the above definition which tangentially contacts outlet stream line F b  at a position of X T  =S T .   
     
     
       3. A stator of a torque converter for vehicles according to claim 1, wherein, with respect to an area adjacent to a trailing edge of a suction side surface of said second stator vane (V 2 ), as viewed in a change of diameter (D T ) of a circle tangentially contacting with both said suction side trailing edge area surface of said second stator vane (V 2 ) and an outlet stream line (F b ) of the working fluid extending from the trailing edge (T 1 ) of said first stator vane (V 1 ), said circle substantially satisfies the following condition, for the purpose of suppressing a separation of the working fluid from said suction side trailing edge area surface of said second stator vane (V 2 ) in the fluid coupling condition, against a shifting thereof between a position of X T  =0.45S T  from the trailing edge (T 1 ) of said first stator vane (V 1 ) and a position where it traverses a cross point (N) of a perpendicular extended from said trailing edge (T 2 ) of said second stator vane (V 2 ) to said outlet stream line (F b ):   (D.sub.T =D.sub.TMIN)/D.sub.TST ≦0.36(X.sub.T /S.sub.T -0.45).sup.1.7     wherein   S T  is a distance from trailing edge T 1  to point N along outlet stream line F b     X T  is a variable expressing distance from point T 1  along outlet stream line F b     D T  is the diameter of the circle according to the above definition which tangentially contacts outlet stream line F b  at X T     D TMIN  is a minimum value of D T     D TST  is the diameter of the circle according to the above definition which tangentially contacts outlet stream line F b  at a position of X T  =S T .   
     
     
       4. A stator of a torque converter for vehicles comprising stator vanes each having such an aerofoil configuration and being arranged in such an array that a pressure side surface of each of said stator vanes adjacent to a leading edge thereof substantially satisfies the following conditions, in terms of a change of diameter (D L ) of a circle tangentially contacting both the pressure side surface of a first one (V 1 ) of said stator vanes adjacent to the leading edge (L 1 ) thereof and an inlet stream line (F a ) directed to the leading edge (L 2 ) of a second one (V 2 ) of said stator vanes, when said circle is shifted from a position of X L  =0.08S L  distant from a cross point (M) at which said inlet stream line (F a ) intersects with a perpendicular extended from the leading edge (L 1 ) of said first stator vane relative to said inlet stream line (F a ) to a position of the leading edge (L 2 ) of said second stator vane, thereby suppressing a separation of working fluid from a surface of the stator vanes in a fluid coupling condition attained after a substantial completion of torque conversion and therearound:   (D.sub.L -D.sub.LMIN)/D.sub.LSL ≦0.38(X.sub.L /S.sub.L -0.08).sup.1.7     wherein     S L  is a distance from point M to leading edge L 2  along inlet stream line F a     X L  is a variable expressing distance from point M along inlet stream line F a     D L  is the diameter of the circle according to the above definition which tangentially contacts inlet stream line F a  at X L     D LMIN  is a minimum value of D L     D LSL  is the diameter of the circle according to the above definition at a position of X L  =S L .   
     
     
       5. A stator of a torque converter for vehicles comprising stator vanes each having such an aerofoil configuration and being arranged in such an array that a suction side surface of each of said stator vanes adjacent to a trailing edge thereof substantially satisfies the following conditions, in terms of a change of diameter (D T ) of a circle tangentially contacting both an outlet stream line (F b ) extended from the trailing edge of a first one (V 1 ) of said stator vanes and the suction side surface of a second one (V 2 ) of said stator vanes, when said circle is shifted from a position of X T  =0.45S T  from the trailing edge (T 1 ) of said first stator vane to a position of a cross point (N) at which said outlet stream line (F b ) intersects with a perpendicular extended from the trailing edge (T 2 ) of said second stator vane relative to said outlet stream line (F b ), thereby suppressing a separation of working fluid from a surface of the stator vanes in a fluid coupling condition attained after a substantial completion of torque conversion and therearound:   (D.sub.T -D.sub.TMIN)/D.sub.TST ≦0.36(X.sub.T /S.sub.T -0.45).sup.1.7     wherein     S T  is a distance from trailing edge T 1  to point N along outlet stream line F b     X T  is a variable expressing distance from point T 1  along outlet stream line F b     D T  is the diameter of the circle according to the above definition which tangentially contacts outlet stream line F b  at X T     D TMIN  is a minimum value of D T     D TST  is the diameter of the circle according to the above definition which tangentially contacts outlet stream line F b  at a position of X T  =S T .   
     
     
       6. A stator of a torque converter for vehicles according to claim 4, wherein a suction side surface of each of said stator vanes adjacent to a trailing edge thereof substantially satisfies the following conditions, in terms of a change of diameter (D T ) of a circle tangentially contacting both an outlet stream line (F b ) extended from the trailing edge of a first one (V 1 ) of said stator vanes and the suction side surface of a second one (V 2 ) of said stator vanes, when said circle is shifted from a position of X T  =0.45S T  from the trailing edge (T 1 ) of said first stator vane to a position of a cross point (N) at which said outlet stream line (F b ) intersects with a perpendicular extended from the trailing edge (T 2 ) of said second stator vane relative to said outlet stream line (F b ), thereby suppressing the separation of working fluid from the surface of the stator vanes in the fluid coupling condition attained after a substantial completion of torque conversion and therearound:   (D.sub.T -D.sub.TMIN)/D.sub.TST ≦0.36(X.sub.T /S.sub.T -0.45).sup.1.7     wherein   S T  is a distance from trailing edge T 1  to point N along outlet stream line F b     X T  is a variable expressing distance from point T 1  along outlet stream line F b     D T  is the diameter of the circle according to the above definition which tangentially contacts outlet stream line F b  at X T     D TMIN  is a minimum value of D T     D TST  is the diameter of the circle according to the above definition which tangentially contacts outlet stream line F b  at a position of X T  =S T .